Interferometer experiment with independent local oscillators

We have operated an interferometer with independent local oscillators and without any communication link of wide bandwidth between the elements of the interferometer. This makes operation possible at very long base lines because, heretofore, construction of the communications link has been the factor limiting the separation of the elements. In our system, coherence at the two elements is maintained through the use of two highly stable, atomic oscillators. The intermediate-frequency output signals are recorded at each element on a high-speed digital tape recorder. Interference fringes are produced later by cross-correlating the two tape records in a digital computer.     

An agent-based approach to modeling impacts of agricultural policy on land use, biodiversity and ecosystem services

We present extensions to the agent-based agricultural policy simulator (AgriPoliS) model that make it possible to simulate the consequences of agricultural policy reform on farmers?? land use decisions and concomitant impacts on landscape mosaic, biodiversity and ecosystem services in a real agricultural region. An observed population of farms is modelled as a multi-agent system where individual farm-agent behaviour and their interactions??principally competition for land??are defined through an optimization framework with land use and landscape impacts resulting as emergent properties of the system. The model is calibrated to real data on the farms and the landscape to be studied. We illustrate the utility of the model by evaluating the potential impacts of three alternative frameworks for the European Union Common Agricultural Policy (CAP) on landscape values in two marginal agricultural regions. Mosaic value was found to be sensitive to the choice of policy scheme in one of the landscapes, whereas significant trade-offs were shown to occur in terms of species richness by habitat and species composition at the landscape scale in both regions. The relationship between food production and other ecosystem services was found to be multifaceted. Thus illustrating the difficulty of achieving landscape goals in a particular region with simple or general land management rules (such as the current rules attached to CAPs direct payments). Given the scarcity of funding for conservation, the level and conditions for allocating direct payments are, potentially, of great importance for preserving landscape values in marginal agricultural regions (subject to levels of other support).     

Characterization of an Insoluble and Soluble Form of Melanin Produced by Streptomyces cavourensis SV 21, a Sea Cucumber Associated Bacterium

Melanin is a widely distributed and striking dark-colored pigment produced by countless living organisms. Although a wide range of bioactivities have been recognized, there are still major constraints in using melanin for biotechnological applications such as its fragmentary known chemical structure and its insolubility in inorganic and organic solvents. In this study, a bacterial culture of Streptomyces cavourensis SV 21 produced two distinct forms of melanin: (1) a particulate, insoluble form as well as (2) a rarely observed water-soluble form. The here presented novel, acid-free purification protocol of purified particulate melanin (PPM) and purified dissolved melanin (PDM) represents the basis for an in-depth comparison of their physicochemical and biological properties, which were compared to the traditional acid-based precipitation of melanin (AM) and to a synthetic melanin standard (SM). Our data show that the differences in solubility between PDM and PPM in aqueous solutions may be a result of different adjoining cation species, since the soluble PDM polymer is largely composed of Mg²⁺ ions and the insoluble PPM is dominated by Ca²⁺ ions. Furthermore, AM shared most properties with SM, which is likely attributed to a similar, acid-based production protocol. The here presented gentler approach of purifying melanin facilitates a new perspective of an intact form of soluble and insoluble melanin that is less chemical altered and thus closer to its original biological form.     

Search for Climatic Models for Forecasting Microtine Outbreaks1

Models for forecasting outbreaks of harmful Microtines are discussed in terms of the three most important types of rodent damage to agriculture and forestry in the European part of EPPO region: problems to field crops by Microtus arvalis and related species, to horticulture and forestry by M. agrestis and some other species, and injury to the underground parts of various crops by Arvicola terrestris. Two models were developed in parallel but independently for M. arvalis, one in the USSR, the other in France; the former approach included M. socialis. A joint Scandinavian project resulted in models for M, agrestis and Clethrionomys glareolus: the outcome is exemplified by the former case and a few comments are given on other types of model development. The probable mechanism of climatic influence through the food chain on the population dynamics of Microtine rodents is discussed and it is concluded that climatic models are a useful tool in planning rodent control strategies. The role of the EPPO Working Party on Field Rodents as a coordinating body in the development of rodent forecasts is also reviewed.     

POSITRON EMISSION TOMOGRAPHY FEATURES OF CANINE NECROTIZING MENINGOENCEPHALITIS

A Yorkshire terrier and a Chihuahua were referred for acute onset, generalized tonic‐clonic seizures and were suspected to have meningoencephalitis based on magnetic resonance (MR) imaging findings. Brain lesions appeared hyperintense with T2‐weighted imaging and hypointense with T1‐weighted imaging, and were characteristic of necrotizing meningoencephalitis. Both dogs were diagnosed with necrotizing meningoencephalitis based on pathologic findings. Fluorine‐18 fluorodeoxyglucose positron emission tomography (FDG‐PET) was performed on both animals before euthanasia with the permission of the owner. In FDG‐PET images, these lesions seen in MR images were characterized by multifocal or diffuse hypometabolism. Our FDG‐PET results provided evidence of glucose hypometabolism in areas of necrosis and cavitation associated with necrotizing meningoencephalitis. FDG‐PET has the potential to provide valuable diagnostic information in dogs with suspected necrotizing encephalitis.     

Analysis of tidal breathing flow volume loop in dogs with tracheal masses

Objectives To investigate whether there are any changes in the tidal breathing flow volume loop (TBFVL) in calm, non-dyspnoeic dogs with intratracheal masses. Methods We compared 4 dogs with intratracheal masses (group 1) with 10 healthy dogs (group 2). Routine clinical and laboratory examinations of the dogs were unremarkable, except for episodic upper respiratory obstructive signs in the dogs in group 1. Lateral radiography of the neck and thorax showed that group 1 dogs had masses that appeared to protrude into the tracheal lumen. Tracheoscopy and surgery or necropsy was performed to confirm the presence of the mass. Arterial blood gas and TBFVL analysis was carried out in all dogs to assess respiratory status. Results The shape of the TBFVL for dogs in group 1 was narrower and ovoid compared with that for the group 2 dogs. Tidal volume and expiratory and inspiratory times were significantly reduced, whereas the respiratory rate was increased for dogs in group 1 compared with dogs in group 2. Arterial blood gas analysis was unremarkable for all dogs. Conclusions TBFVL is a non-invasive technique that is easy to perform and well tolerated by dogs. In the absence of abnormalities detected by routine diagnostic evaluations and arterial blood gas analysis in dogs with intratracheal masses, the TBFVL contributes to the definition of the physiologic status of the airways at the time of testing, and results suggests that these dogs breathe quite normally when they are calm and non-dyspnoeic.     

Allelopathic potential of K21, selected as a promising allelopathic rice

The agronomic characteristics of a newly bred potent allelopathic rice, K21, including morphological appearance, resembled its female parent, Dongjinbyeo, except for 8 days' earlier heading and 9 cm shorter plant height. The water extract of K21 showed a greater inhibitory effect on the shoot and root growth of barnyardgrass than its female parent, but less than the male parent, Kouketsumochi. At the highest extract concentration of 5.0%, the inhibitory effect of K21 on the shoot growth of barnyardgrass was ≈ 64%, similar to its male parent. The dry weight of the barnyardgrass shoot was reduced by 13.0% when grown with K21 and 30.2% when grown with its male parent. There was no inhibitory effect on the shoot dry weight of barnyardgrass when grown with the female parent. The activity of cinnamic acid 4-hydroxylase in K21 was ≈ 1.8-fold higher than that of the female parent, but significantly lower than that of the male parent. The ρ-coumaric acid content in K21 was ≈ 60% higher than that of the female parent, but it was about half of the male parent. The total amount of phenolic compounds in K21 was ≈ 11.5% higher than in the female parent, but about half of the male parent. The results obtained suggest that the newly bred K21 contains desirable allelopathic traits derived from the male parent, Kouketsumochi, and acceptable agronomic traits from its female parent, Dongjinbyeo.